Bartlett weather in August

In August, Bartlett sees average daytime highs of 80°F and overnight lows near 62°F, with 3.7 in of rain across 10.6 wet days and about 13.7 hours of daylight. It is the 2nd-warmest and 5th-wettest month of the year here.

Day-to-day highs hold fairly steady near 80°F through the month. The sky is clear or mostly clear about 35% of the time in August, and the air most often feels comfortable.

Daylight stretches from about 14 h 18 min at the start of August to 13 hours by month's end. Set against the rest of the year, August is Bartlett's 2nd-clearest and 12th-windiest month. For the whole year in context, see Bartlett's year-round climate.

Daytime high
80°
2nd warmest
Overnight low
62°
11th coldest
Rainfall
3.7 in
10.6 wet days
Daylight
13 h 42 min
5:06 AM – 6:48 PM
Cloud cover
55%
2nd clearest
Wind
6 mph
12th windiest
Solar energy
5.38 kWh/m²
Travel score
6.5
out of 10

Bartlett is village straddling Cook, DuPage and Kane Counties in Illinois, United States of America.

Density
1,011/km²
people per km²
Founded
1891

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 80°F through the month.

A typical August day in Bartlett reaches about 80°F in the afternoon and slips back to 62°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 73°F and 88°F. Set against its neighbours, August runs about 2°F cooler than July and about 7°F warmer than September.

50°60°70°80°90°151015202531
Avg high (°F)Avg low (°F)
18264
28264
38164
48164
58164
68164
78163
88163
98163
108163
118063
128063
138063
148063
158063
168063
178062
188062
198062
208062
218062
228062
238062
248062
258062
268062
277961
287961
297961
307961
317960

How August really feels in Bartlett

Once humidity and wind are folded in, August averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

August sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Bartlett weather by month

How August compares with the rest of the year at a glance. August is the 2nd-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan30° / 16°2.17.95.79.30.0
Feb34° / 20°1.974.910.30.0
Mar46° / 29°2.69.63.111.71.4
Apr58° / 39°4.512113.14.1
May69° / 50°4.612.5014.36.0
Jun79° / 60°4.212.30156.3
Jul82° / 65°3.711.2014.76.1
Aug80° / 62°3.710.6013.76.5
Sep74° / 55°3.18.4012.37.1
Oct61° / 43°3.190.210.95.2
Nov47° / 32°2.481.59.61.5
Dec35° / 22°2.284.490.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 19% of August, with mostly cloudy or overcast conditions the remaining 46%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15248
25248
35248
45248
55347
65347
75248
85248
95248
105248
115248
125248
135248
145248
155347
165347
175446
185446
195347
205446
215347
225446
235446
245545
255545
265545
275743
285743
295743
305842
315941

Chance of precipitation in August

Any precipitation

Bartlett gets around 3.7 in of rain over 10.6 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 34% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
134
234
334
434
534
634
734
834
934
1034
1134
1235
1335
1435
1535
1636
1736
1836
1936
2035
2135
2235
2335
2434
2533
2632
2732
2831
2930
3029
3129

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

Most of August feels comfortable — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, August lands in the comfortable band about 26% of days. Sticky, muggy-or-worse air turns up on roughly 35% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
112252525131
212252525121
312262525121
412262525120
512262524120
612262524120
712262524120
813262623120
913262623120
1013262623120
1113262623120
1214262623120
1314262623120
1414262623110
1514262623110
1614252723110
1714252724100
1814252724100
1914252725100
2014252725100
2114252725100
2214252625100
231425262590
241425262590
251526262590
261526252590
271626252490
281727252380
291827242380
301927242280
312028232170

Wind in August

Winds average 6 mph in August, the calmest month.

Across August, daily wind ranges from about 6 mph on the calmest days to 6 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 18 min at the start of August to 13 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 78 minutes over August. Sunrise moves from 4:50 AM to 5:22 AM, and sunset from 7:08 PM to 6:24 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.34:507:08
214.34:517:07
314.24:527:05
414.24:537:04
514.24:547:03
614.14:557:02
714.14:567:01
814.04:576:59
914.04:586:58
1014.04:596:57
1113.95:006:55
1213.95:016:54
1313.85:026:53
1413.85:036:51
1513.85:046:50
1613.75:066:48
1713.75:076:47
1813.65:086:45
1913.65:096:44
2013.55:106:42
2113.55:116:41
2213.45:126:39
2313.45:136:37
2413.45:146:36
2513.35:156:34
2613.35:166:32
2713.25:176:31
2813.25:186:29
2913.15:196:27
3013.15:216:26
3113.05:226:24

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.38 kWh/m².

For context, solar energy here swings from a low near 1.62 kWh/m² to a high of 6.3 kWh/m² in June across the year — August's 5.38 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.9Bright
25.8Bright
35.8Bright
45.8Bright
55.7Bright
65.7Bright
75.7Bright
85.6Bright
95.6Bright
105.5Bright
115.5Bright
125.5Bright
135.4Bright
145.4Bright
155.4Bright
165.3Bright
175.3Bright
185.3Bright
195.3Bright
205.3Bright
215.2Bright
225.2Bright
235.2Bright
245.2Bright
255.1Bright
265.1Bright
275.1Bright
285.1Bright
295.0Bright
305.0Bright
315.0Bright
Planning a trip in August

Is August a good time to visit Bartlett?

Our two travel scores rate August for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.5
Sightseeing
2nd-best month of the year
6.6
Beach & pool
2nd-best month of the year

August is a reasonable time to visit Bartlett for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Bartlett in August

From August's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In August, Bartlett sees daytime highs around 80°F and nights near 62°F. Worth packing: light clothes, rain gear and sun protection. About 11 days see rain.

light clothesrain gearsun protection

Sea temperature near Bartlett in August

The nearest coast averages about 73°F in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 30 mi away) is warmest in August at about 73°F and coldest in February near 36°F.

It's comfortable for a long swim from Jul 13 to Sep 15 — about 2.1 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°F)Comfort
Jan38Bracing
Feb36Bracing
Mar36Bracing
Apr39Bracing
May45Bracing
Jun57Bracing
Jul70Refreshing
Aug73Refreshing
Sep68Refreshing
Oct58Bracing
Nov49Bracing
Dec42Bracing

UV index in Bartlett in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Bartlett peaks around June 23 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 23UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May7Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low

Air quality in Bartlett in August

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where August falls, not just the annual average.

Air quality in Bartlett is worst in July — around 17 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (October, 9 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodJul 1817 µg/m³Oct 229 µg/m³
PM2.5 (µg/m³)Level
Jan12Moderate
Feb15Moderate
Mar16Moderate
Apr14Moderate
May15Moderate
Jun16Moderate
Jul17Moderate
Aug16Moderate
Sep13Moderate
Oct9Good
Nov10Good
Dec11Good
Location & terrain

Where is Bartlett?

Bartlett sits at 42.0°N, 88.2°W, 810 ft above sea level, in United States. The nearest listed city is Hanover Park, 1.9 mi away.

Topography around Bartlett

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Bartlett.

Within 2 miles, the terrain around Bartlett has only modest variations in elevation — a maximum elevation change of 161 ft around an average of 807 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 364 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 892 ft.

The land around Bartlett is covered by trees (36%), artificial surfaces (33%) and grassland (26%) within 2 miles, trees (38%), artificial surfaces (30%) and grassland (26%) within 10 miles, and cropland (37%) within 50 miles.

2 miles
161 ft
10 miles
364 ft
50 miles
892 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Hanover Park 1.9 mi · Streamwood 1.9 mi · South Elgin 5.6 mi · Roselle 5.6 mi · Elgin 5.6 mi · Schaumburg 5.6 mi · Bloomingdale 6.2 mi · Carol Stream 6.2 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Bartlett (41.995°, -88.1856°, elevation 810 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).